mqadonfg.dll is a worm W32.PPdoor-R. mqadonfg.dll opens a back door. mqadonfg.dll spreads via open network shares. Related files: %System%\arpo412.exe %System%\mqadonfg.dll %System%\winrpmsg.dll %System%\wndfxyfi.dll %System%\hgakheg.dll %System%\vjoytl32.dll More info: http://www.sophos.com/virusinfo/analyses... Removal: Remove mqadonfg.dll from Windows startup using antivirus (also check How To Remove section)Startup Optimizer.